A flag flies over the finish line as medical workers aid injured people following an explosion at the finish line of the 2013 Boston Marathon in Boston, Monday, April 15, 2013. Two explosions shattered the euphoria at the finish line, sending authorities out on the course to carry off the injured while the stragglers were rerouted away from the smoking site of the blasts.

Terrorists want people to believe they are powerful and ominous. In reality, they are small groups whose ideas do not resonate with public opinion. We cannot let them destroy what this country holds dear.

They cannot be allowed to win, these fanatics who would destroy the nation’s sense of peace and security, of community and of the freedom to gather.

Monday’s horrific and tragic bombings near the finish line of the Boston Marathon and at a library later in the day, were cowardly attacks on innocent people, including children enjoying the festivities with their parents. We mourn with those who are suffering.

This was an assault on tradition. One, we don’t doubt, that was well calculated. Consider:

The annual race coinciding with Patriots’ Day in Boston began in 1897 and has become an important part of that area’s sense of community, spanning generations. Patriots’ Day itself is a commemoration of the battles of Lexington and Concord, key moments in the Revolutionary War that established freedom.

While participants in this marathon must qualify to participate, such races are unique in that they are major sporting events involving thousands of regular people who, other than the few elite runners at the front of the pack, otherwise receive little athletic notoriety. More than 25,000 runners were estimated to have taken part in Monday’s event. For many, doing so was the fulfillment of a personal goal requiring long hours of sacrifice and work — a once-in-a-lifetime accomplishment meant, perhaps, to inspire others.

All of the above may have been reasons why whoever planted the bombs did so, just as those who plotted the 9/11 attacks chose iconic buildings as targets. Monday’s race began with a moment of silence for the victims of the massacre at Newtown, Conn., which also compounds this tragedy. The bombs were detonated four hours after the race started, meaning they were meant to target average runners, not the elite who typically finish in about two hours. It was an assault against everyday people enjoying themselves.

Terrorism is the means by which people with feeble ideas that otherwise can’t win majority support make themselves seem larger than life. It is a way for them to entertain ideas of bringing free nations to their knees while instilling fear at every turn.

Americans cannot let that happen.

There is, of course, a line between carrying on as normal and taking prudent precautions. The Salt Lake Marathon is scheduled for this weekend. Organizers would be wise to take extra precautions, perhaps even isolating the finishing line. The local event may not be a natural target for high-profile attacks, but deranged copycats often are inspired by such events.

Judging by early accounts, first responders in Boston did a heroic job. They broke through barriers and provided immediate aid to the injured, as did many bystanders. They deserve praise and support.

As events unfold in coming days, the picture will become clearer as to what happened and who was responsible. No one should doubt that this nation’s enemies have been trying for nearly 12 years to follow up the 9/11 attacks, but it is possible a person or group other than those affiliated with well known terrorist organizations set the bombs.

Regardless, the nation cannot abandon its public traditions, gatherings or celebrations. It cannot let fanatics set the rules.

Horrific crimes have a way of uniting people and accentuating common goodness. The United States is a uniquely free land. It must battle this evil without abandoning what it holds dear.